增加cell swipe组件 (#39)

* add cell swipe

* cell swipe

* bugfix

* test

* style

src/utils/dom.js

@@ -55,3 +55,44 @@ export function removeClass(el, cls) {
     el.className = trim(curClass);
   }
 };
+export const once = function(el, event, fn) {
+  var listener = function() {
+    if (fn) {
+      fn.apply(this, arguments);
+    }
+    off(el, event, listener);
+  };
+  on(el, event, listener);
+};
+
+export const on = (function() {
+  if (document.addEventListener) {
+    return function(element, event, handler) {
+      if (element && event && handler) {
+        element.addEventListener(event, handler, false);
+      }
+    };
+  } else {
+    return function(element, event, handler) {
+      if (element && event && handler) {
+        element.attachEvent('on' + event, handler);
+      }
+    };
+  }
+})();
+
+export const off = (function() {
+  if (document.removeEventListener) {
+    return function(element, event, handler) {
+      if (element && event) {
+        element.removeEventListener(event, handler, false);
+      }
+    };
+  } else {
+    return function(element, event, handler) {
+      if (element && event) {
+        element.detachEvent('on' + event, handler);
+      }
+    };
+  }
+})();